Electrostatic Origins of CO2-Increased Hydrophilicity in Carbonate Reservoirs

Injecting CO2 into oil reservoirs appears to be cost-effective and environmentally friendly due to decreasing the use of chemicals and cutting back on the greenhouse gas emission released. However, there is a pressing need for new algorithms to characterize oil/brine/rock system wettability, thus better predict and manage CO2 geological storage and enhanced oil recovery in oil reservoirs. We coupled surface complexation/CO2 and calcite dissolution model, and accurately predicted measured oil-on-calcite contact angles in NaCl and CaCl2 solutions with and without CO2. Contact angles decreased in carbonated water indicating increased hydrophilicity under carbonation. Lowered salinity increased hydrophilicity as did Ca2+. Hydrophilicity correlates with independently calculated oil-calcite electrostatic bridging. The link between the two may be used to better implement CO2 EOR in fields

Seroepidemiology Of Human Cytomegalovirus In Pregnant Women and their Neonates In Kerman City During 2005

Abstract: Introduction: Human Cytomegalovirus (HCMV) or Human Herpes Virus Type-5(HHV-5) is a member of herpesviridae placed in subtype beta herpesvirinae. CMV is a ubiquitous pathogenic virus and can infect humans all through their life. Prevalence of CMV infection in developed countries is about 45% and in developing countries it varies up to 100%. CMV infection during pregnancy is very important, because it can threat life of both mother and her fetus, and it can cause congenital defects. Maternal infection is a determining factor in neonatal infection. The present study was conducted to determine the prevalence rate of CMV infection as well as the relationship between underlying factors of this infection in women and their neonates in Kerman. Methods: ELISA technique and Diagnostic Kits (EIA WELL, Rome, Italy) were used to determine the seroprevalence of 794 samples (397 maternal, 397 neonatal) collected from 5 delivery centers in Kerman. Results: The frequency distributions of maternal primary infection, secondary infection, immune mothers and seronegative cases were respectively 0.76% (3 cases), 32.24% (128 cases), 59.7% (237 cases) and 7.3% (29 cases). Seroprevalence rate for CMV-IgG and CMV-IgM of mothers were respectively, 33.8% (134 cases) and 91.94% (365 cases). No significant relationship was found between CMV infection and factors of mother’s age and occupation, husband’s occupation, number of children, parity, family income, previous history of abortion, pervious history of blood transfusion and organ transplant, febrile disease during pregnancy and place of residency; however, mother’s educational level showed a significant relation (P=0.38). Conclusion: Due to high prevalence rate of CMV found in this study, further studies about the diagnosis, epidemiology and detection of CMV primary infections in mothers and their neonates, are highly recommended. . Keywords: HCMV, Seroepidemiology, Maternal Infection, Primary Infection, Secondary Infection, ELIS

Identification of chemical components in Zataria multiflora callus by GC-Mass analysis

Background and objectives: A modern biotechnological technique to obtain useful natural products from plants is to isolate them from their callus. Zataria multiflora is a bushy herb of the Lamiaceae family known for its stimulant, antibacterial, antioxidant and expectorant effects in Iranian folk medicine.  The present study has investigated the induction of callus tissue and identification of its chemical compounds by GC-Mass analysis. Methods: The plant seeds of were sterilized and cultured in petri dishes lined with MS medium. After the emergence of seedlings, leaf segments were transferred to another MS medium supplemented with 2 mg/L 2,4- Dichlorophenoxyacetic acid + 1 mg/L  Kinetin. The petri dishes were incubated in a growth chamber at 24 °C with photoperiod of 16/8 (light/dark). The methanol extract of the calli were extracted after 2 month of callus induction and the chemicals were analyzed by gas chromatography-mass spectrometry (GC-MS). Reults: GC-MS analysis showed 20 different compound including different fatty acids, phytosterolls and phenolic compounds. Linolenic acid methyl ester (13.38%), thymol (10.34%), cyclohexasiloxane dodecamethyl (7.50%) and р-cymen (7.30%) were the dominant compounds, respectively. Conclusion: This novel   finding showed that in vitro production of thymol and other terpenoids by callus culture could be optimized for wide industrial and pharmaceutical applications via bioreactor systems employment

Optimization of callus induction of Zataria multiflora under the effect of different plant growth regulators and explant source

Background and objectives: The Lamiaceae family is rich in favorable secondary metabolites which have different medicinal properties and also use in food, cosmetic and sanitary industry. Zataria multiflora Boiss. is an aromatic and bushy plant containing specific pharmaceutical components which is only distributed in certain regions of Iran. Tissue culture technologies could be suitable for in vitro production of Zataria. Methods: In this study, callus production and callus related traits of Zataria was evaluated at in vitro condition. Callus induction was performed on Murashige and Skoog (MS) medium containing different levels of plant growth regulators including different cytokinins (Kinetin, benzyl amino purine) and auxins (2,4 dichlorophenoxyacetic acid and naphtalen acetic acid) and two different explant (hypocotyl and leaf). Results: The friable calli with yellow-green color only appeared from leaf explants on three different treatments including: 1: 2.5 (mg/L 2,4-D); 2: 2 (mg/L  2,4-D); 3: [2 (mg/L) 2,4-D+ 1 (mg/L Kin].  The best callus induction (75%) was obtained at 2,4-D (2 mg/L ) + Kin (1 mg/L) after 2 month of incubation under the photoperiod of 16/8 (light/dark). The highest callus growth rate (CGR) (0.072 mm/day) and callus fresh weight (0.135 g) were denoted to the treatment of 2 mg/L (2,4-D).  Conclusion: The benefits of the protocol described here include the possibility of its use throughout the callus culture for commercial production of suitable secondary metabolites of Zataria in rapid time and huge scale

Liquefaction Risk Potential of Road Foundation in the Gold Coast Region, Australia

Soil liquefaction is a major concern for infrastructures constructed on saturated cohesionless soils in the event of an earthquake. This paper examines the liquefaction potential of the road foundations in twenty sites located in Gold Coast of South East Queensland. The preliminary seismic analysis was carried out in accordance with Seed and Idriss (1971) simplified procedure by using the in-situ SPT data. The factors of safety (FS) was calculated for three different moment magnitudes of Mw = 3, 4 and 5, and the analysis was used to generate the Liquefaction Potential Index (IL) and Liquefaction Risk Index (IR) values for all sites. The calculated indexes are used to delineate the liquefaction resistance of the road foundations. The study shows that all cases were found to have low liquefaction failure potential for the moment magnitudes considered in the study.Griffith Sciences, Griffith School of EngineeringFull Tex

A Review of Electrokinetic Treatment Technique for Improving the Engineering Characteristics of Low Permeable Problematic Soils

The use of electrokinetic (EK) treatment which is a comparatively new methodology is being investigated in some parts of the world as a viable in situ soil remediation and treatment method. The principles of EK treatment method involve applying a low direct current or a low potential gradient to electrodes inserted in the low permeable soils that cannot readily drained. The transportation of charged species across the soil involves several complex mechanisms such as electrolysis, electro-osmosis, electro-migration and electrophoresis. This technique can also be applied/enhanced by introducing desirable non-toxic chemical compounds such as lime or cement solutions to the soil by introducing them at the appropriate electrode. The combined effect of these processes together with various geochemical reactions alters the chemical composition of the soil porous medium and thereby alters the physicochemical properties of the soil. Although the technology has been approved to be practical in many laboratory bench scale experiments and small-scale pilot field tests, complicated features such as many electrochemical reactions and soil contaminant interactions are still not fully understood, therefore there is a need for further research to be conducted for a better understanding of physicochemical changes in problematic soils and efficiency of this newly developed technology.Griffith Sciences, Griffith School of EngineeringFull Tex

Laboratory evaluation of physico-chemical variations in bentonite under electrokinetic enhancement

When the traditional ground improvement techniques are not practical for a particular situation, alternative technology, such as electrokinetic (EK) soil treatment can be considered. EK treatment method involves applying a low direct current (DC) or a low potential gradient to arrays of electrodes inserted in the low permeable soils simulating migration of electricity, pore water, ions and charged particles across the soil, hence modifying the physicochemical, mechanical and engineering properties of the soil. This study investigates the effects of EK treatment on conductance phenomena and physico-chemical changes of bentonite at different intervals under total applied voltage of 10V subjected to specific types of anode enhancement solutions. The cumulative electroosmotic flow and electric current through the sample was measured for 15 days of treatment. The specimens were also tested for moisture content, pH and undrained shear strength variations over different time periods of 3, 6, 9, 12 and 15 days showing good correlations between the soil parameters.Griffith Sciences, Griffith School of EngineeringFull Tex

Laboratory investigation on Physico-chemical Changes in Kaolinite during Electro-Kinetic Treatment Subjected to Enhancement Solutions

Electro-kinetic (EK) treatment is an emerging technique, which uses low intensity direct electric current or a low electric potential difference, to improve the engineering properties of subsurface soils while having minimum disturbance to the surface. This study aims to investigate the effects of EK treatment on conductance phenomena and some physico-chemical changes of kaolinite soil at different intervals under total applied voltage of 10V subjected to specific types of anode enhancement solutions under the coupled chemical, hydraulic and electrical (CHE) gradient. The cumulative electro-osmotic flow and electric current through the sample was measured for period of 15 treatment days. Subsequently the specimens were tested for moisture content, pH and undrained shear strength variations over different time periods (3, 6, 9, 12 and 15 days) showing very good correlations between them.Griffith Sciences, Griffith School of EngineeringFull Tex

Characterization of highly compressible marine clay for road foundation

Soft clay soils are commonly found in many parts of the Asia Pacific. This paper will first provide a literature review of the problematic soils in several regions in the Asia Pacific with the aim for gathering geotechnical knowledge for road foundation design. The main objective of this paper is to study the characteristics of marine clay in Northwestern Peninsular Malaysia based on field and laboratory test data gathered from the ground investigations. The sub-soils in the Northwestern Peninsular Malaysia consist of sedimentary soil deposits which form alternate layers of clay and sand. New empirical relations between the soil index properties and compressibility properties are presented. Regression analyses and statistical t test method are conducted on the empirical relationships for predicting the compressibility behaviors of marine clay in the study area. The statistical t test conducted for Cc and Cr data shows significant and non-significant deviation between the predicted and the actual field data respectively.Griffith Sciences, Griffith School of EngineeringNo Full Tex

A study of the performance of the LSWA CO2 EOR technique on improvement of oil recovery in sandstones

Low salinity water is an emerging enhanced oil recovery (EOR) method that causes wettability alteration towards a favorable state to reduce residual oil saturation, while water alternating gas (WAG) is a proven EOR process that enhances oil recovery by controlling mobility of both water and gas. Therefore, combining the two EOR processes as low salinity water-alternating CO2 EOR injection (LSWA CO2) can further improve oil recovery by promoting the synergy of the mechanisms underlying these two methods.Core flooding experiments, contact angle, interfacial tension (IFT), and CO2 solubility measurement in oil and brine were conducted to investigate the viability and performance of LSWA CO2 in sandstone reservoirs. A favorable wettability alteration, along with IFT reduction and mobility control, are the mechanisms that contribute to residual oil mobilization efficiencies during the LSWA CO2 EOR process. In addition, LSWA CO2 core flooding experiments result in a significant incremental oil recovery.Three smart waters were tested in our research, to examine the impact of changing cationic composition on oil recovery. The solutions are designed brines as NaCl (SW1), MgCl2 (SW2), and KCl (SW3). Of the three solutions, SW1 yields the highest incremental oil recovery and highest IFT reduction. In addition, it results in a favorable wettability alteration towards a more water-wet state.In all cases, introducing CO2 to the brine/oil system shows a great advantage in terms of enhancing wettability modification, promoting IFT reduction, and controlling the displacement front of the injected fluid through mobility control